A lesson on building mock-ups using recycled materials for the Sec 2 DT project on RG machine

1. Sec 2 DT project: RG
machine
Building a mock-up using recycled materials

2. By the end of the lesson, students are able to:
• use the critical dimensions given to build mechanisms for the RG
machine using recycled materials

3. Critical dimensions needed before making the
mechanism
Pegboard dimensions
295 mm
12 peg holes
420 mm
16 peg holes
Marble diameter = 15 mm

4. Critical dimensions needed before making the
mechanism
Horizontal distance
between peg holes
= 20 mm
Vertical distance
between peg holes
= 20 mm

5. After having the critical dimensions
1. Plan the path using the dimensions given
2. Consider which mechanism to build for the mock-up
3. Prepare recycled materials such as tissue box, shoe box, toilet roll, plastic bottles for cardboard modelling
Shoe box Toilet roll Tissue box

6. Examples of mechanism that can be done
using recycled materials
Inclined plane Wheel and axle Screw mechanism

7. Examples of mechanism that can be done
using recycled materials
Wedge Screw mechanism using plastic bottle Pulley

8. Questions to ask yourself when doing mock-
up
• How does the overall path look like and what are the dimensions of
the path?
• Can the mechanism fit in the pegboard?
• Can the mechanism function as intended?
• What are the measurements of each mechanism?
• How do you ensure safety when doing mock-up?

9. How to cut cardboard using a penknife
• https://www.youtube.com/watch?v=KFJb_ikQpRU
• https://www.youtube.com/watch?v=HRmJ7yD3ZnE
How to join cardboard together

10. Useful video resources
• https://www.youtube.com/watch?v=MyphMV2wPAk
• https://www.youtube.com/watch?v=D_jGExZxq1Q

11. After completion of mechanism
• Take a photo of the completed mechanism and email to your
respective teacher
• Assemble the mechanism(s) to the pegboard when you are back in
school
• Test the mechanism(s) with a marble
• Does the RG machine work well?
• Evaluate and modify the mechanism accordingly